纳米钒酸铋的微波快速合成及光催化性能研究

采用微波辅助加热法以NaVO₃溶液和Bi(NO₃)₃·5H₂O的硝酸溶液为反应物，在10～40 min内合成了纳米钒酸铋粉末。利用XRD、FTIR、TEM、UV-Vis等手段研究了反应时间对产物结构及形貌的影响。经测定反应10 min时，得到纯的四方相BiVO₄，随着反应时间的延长，逐渐出现单斜相的衍射峰，当反应40 min时，获得纯的单斜相BiVO₄。同时XRD和IR结果证明了相转变的过程。TEM分析表明不同的反应时间条件下样品呈现不同的形貌。不同反应时间下获得样品的光催化性能的结果表明，微波反应时间对BiVO₄结构的转变及光催化性能的改变起到了重要的作用。

Nanocrystalline BiVO4:Preparation by Microwave Irradiation and Photocatalytic Properties

Nanocrystalline BiVO₄ powders were prepared from aqueous Bi(NO₃)₃ and NaVO₃ solution by a rapid microwave-assisted method with accurate controlled of microwave irradiation time. The properties of the synthesized BiVO₄ powders were investigated by XRD, FTIR, TEM and UV-Vis. When heating 10 min by microwave, pure tetragonal BiVO₄ can be obtained. The highly crystalline phases converted irreversibly from tetragonal to monoclinic BiVO₄ with prolonged irradiation time. When heating above 40 min by microwave, pure monoclinic BiVO₄ can be obtained. X-ray diffraction and FTIR measurements proved the phase transition of BiVO₄. These variations in phase structures result in different photocatalytic properties under visible light.